NORWELL — As gray clouds hovered heavily and a drizzle fell in Norwell Saturday morning, North and South Rivers Watershed Association executive director Samantha Woods pulled out her smartphone.
The association’s 22d annual Great River Race was about to begin, and the weather map on Woods’s phone showed green patches in southern Massachusetts, indicating light rain.
She pointed to a red blotch of heavy rain and said as long as it didn’t move to the Norwell area, the race would be fine.
“We’re going to get wet regardless,” Gregory Keches of Boston said as he prepared his kayak for the start of the race at the Union Street bridge on the Marshfield-Norwell line to the Hanover-Pembroke town border about 7 miles upstream.
The foul weather turned out to be a blessing for the 56 people who took part in the race: It kept the rowers cool and at a reasonable number.
“It made it more manageable than two years ago [when there were] about 90 boats,” Paula Christie, the association’s assistant director, said of the 43 boats that started on the course.
The race drew area residents young and old and even a few rowers from other states, including Rhode Island and North Carolina.
Before the race, people chatted about the weather and zipped on their life vests, and three young men took out an essential tool to get their kayak ready: duct tape.
David Arruda, 26, Alex Russo, 22, and Brett Muirhead, 20, got the idea to build a kayak out of duct tape from “MythBusters.” As they began what they called their “late-night build sessions,” the Billington Sea Kayak co-workers decided to use the unusual boat — bright pink and silver made entirely out of duct tape and PVC pipes — to raise money for Stand Up To Cancer, a charitable organization that funnels funds to cancer research.
By Saturday morning, Arruda, Russo, and Muirhead had raised about $650.
Russo, the one chosen to row the boat during the race, wasn’t certain how it would hold up on the hour-plus voyage.
“Unexpected leaks are not welcome,” he said with a laugh.
But the 55-pound vessel “defied a lot of people’s expectations,” he said, after it crossed the finish line a little more than an hour and a half later.
“It was an interesting journey for sure,” Russo said. “Compare it to a Toyota Corolla in a NASCAR race.”
Other competitors praised the beauty of the course and the work the North and South Rivers Watershed Association does with the funds it raises from the race, which costs rowers $30 to $40 per boat, depending on when they registered and how many people were in the craft.
“The money helps our organization’s efforts to help support and protect our rivers,” Woods said.
Nancy Lamarre, 74, and her husband, Jack, 76, have been coming from Bakersville, N.C., to take part in the race for nine years.
“They’re in the senior citizen category and they always slaughter everybody,” Christie said before the boats took off.
And they did. Jack beat 15 other men in the Kayak Single Men category with a time of 1 hour and 2 minutes, and Nancy placed second in the Kayak Single Women category with a time of 1 hour and 14 minutes.
“We race here, there, and everywhere,” Jack Lamarre said before they loaded their kayaks onto their car. “And this is one of our favorites.”